Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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Evaluation of Bond Strength for FRP Hybrid Bar According to Coating Methods using Silica Sands

규사 코팅 방법에 따른 FRP Hybrid Bar의 부착강도 평가

  • Jung, Kyu-San (Korea Institute of Civil Engineering and Building Technology) ;
  • Park, Ki-Tae (Korea Institute of Civil Engineering and Building Technology) ;
  • You, Young-Jun (Korea Institute of Civil Engineering and Building Technology) ;
  • Seo, Dong-Woo (Korea Institute of Civil Engineering and Building Technology) ;
  • Kim, Byeong-Cheol (Korea Institute of Civil Engineering and Building Technology) ;
  • Park, Joon-Seok (Korea Institute of Civil Engineering and Building Technology)
  • 정규산 (한국건설기술연구원 구조융합연구소) ;
  • 박기태 (한국건설기술연구원 구조융합연구소) ;
  • 유영준 (한국건설기술연구원 구조융합연구소) ;
  • 서동우 (한국건설기술연구원 구조융합연구소) ;
  • 김병철 (한국건설기술연구원 구조융합연구소) ;
  • 박준석 (한국건설기술연구원 구조융합연구소)
  • Received : 2017.09.29
  • Accepted : 2017.12.08
  • Published : 2017.12.31
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Abstract

In this study, we examined the bond performance of FRP Hybrid Bars. FRP Hybrid Bars are developed by wrapping glass fibers on the outside of deformed steel rebars to solve the corrosion problem. The surface of the FRP Hybrid Bars was coated with resin and silica sand to enhance its adhesion bonding performance with concrete. Various parameters, such as the resin type, viscosity, and size of the silica sand, were selected in order to find the optimal surface condition of the FRP Hybrid Bars. For the bonding test, FRP Hybrid Bars were embedded in a concrete block with a size of 200 mm3 and the maximum load and slip were measured at the interface between the FRP Hybrid Bar and concrete through the pull-out test. From the experimental results, the maximum load and bond strength were calculated as a function of each experimental variable and the resin type, viscosity and size of the silica sand giving rise to the optimal bond performance were evaluated. The maximum bond strength of the specimen using epoxy resin and No. 5 silica sand was about 35% higher than that of the deformed rebar.

본 논문은 FRP Hybrid Bar의 최적 부착 성능 도출을 위한 실험 결과를 나타낸다. FRP Hybrid Bar는 이형 철근의 부식문제를 해결하기 위하여 이형 철근 외측에 유리섬유를 감싸 만들어졌다. 콘크리트와의 부착 성능 향상을 위해 매끈한 FRP Hybrid Bar 표면에 수지와 규사를 이용하여 코팅하였고 수지의 종류 및 점도, 그리고 규사의 크기를 실험 변수로 하여 FRP Hybrid Bar의 부착 성능을 실험적으로 평가하였다. FRP Hybrid Bar의 부착 성능 평가를 위해 한 변의 길이가 200 mm인 정육면체 콘크리트 블록에 FRP Hybrid Bar를 매립하였고, 인발 실험을 통하여 FRP Hybrid Bar와 콘크리트의 계면에서의 최대 하중과 슬립을 측정하였다. 실험 결과로부터, 각 실험 변수에 따른 최대 하중 및 부착 강도를 산정하였고 FRP Hybrid Bar의 부착 성능이 가장 우수한 수지 종류 및 점도, 그리고 규사 크기를 도출하였다. 에폭시 수지와 5호 규사를 사용한 실험체의 최대부착강도는 이형철근의 최대부착강도 대비 약 35% 정도 증가되었다.

Keywords

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